- Flood network
- Block port
- Waste resources
Denial-of-service attacks prevent use of a service by its authorized users. A denial-of-service attack can come in different forms. They may be generated from outside or from within an information technology system. Attackers may "flood" a network with large volumes of data. They can overwhelm specific ports so no traffic can pass. Denial-of-service attacks may require the computer to attend to an endless list of requests, consuming all its processing power in a useless effort. System and network administrators must be vigilant for advance indicators of a denial of service attack, or a distributed denial of service attack, which originates from a multitude of different computers.